Clock and similar indicator



April 29, 1930.

A. F. POOLE CLOCK AND SIMILAR INDICATOR Filed Jan. 6, 1927 4Sheets-Sheet l A TTQ/P/VE) April 29, 1930. POOLE 1,756,437

CLOCK AND SIMILAR INDICATOR Filed Jan. 6, 1927 4 Sheets-Sheet 2 TTOP/VEKApril 29, 1930. r A. F. POOLE 1,756,437

CLOCK AND SIMILAR INDICATOR I Filed Jan. 6, 1927 4 Sheets-Sheet 3'IIIIIIII'IIIIII A TTO/ F/VEZ April 29, 1930. POOLE 1,756,437

CLOCK AND SIMILAR INDICATOR Filed Jan. 6, 1927 '4 Sheets-Sheet 4ATTO/Q/VEK Patented Apr. 29, 1930 UNITED STATES PATENT OFFICE ARTHUR I.POOLE, OF ITHACA, NEW YORK, ASSIGNOR TO POOLE MANUFACTURING 00.,

INC., A CORPORATION OF NEW YORK CLOCK AND SIMILAR INDICATOR Applicationfiled January 6, 1927. Serial No. 159,323.

This invention relates to electric clocks and the like, and is in thenature of an improvement upon the type of electric clock disclosed andclaimed in my prior co-pending application, Serial Number 685,387, filedJanuary 10, 1924. In electric clocks of the type disclosed in said priorapplication, an impulse element is normally held in poised position andis released to impart a propelling force to an oscillating memberdriving the time train whenever the amplitude of oscillation of saidoscillating member falls below a given value, thus increasing theamplitude and causing a continuance of operation of the time train.

One object of the invention is to improve and simplify the control ofsaid impulse element and its restoration to poised position.

A further object of the invention is to provide improved controlling andresetting means for the impulse element which will be relativelycompact, simple, durable and inexpensive in construction which may beformed largely-from stamped sheet metal; which will be dependable andprecise in action; with which arcing of the contacts controlling theelectric circuit may be avoided; which will be exceptionally silent inoperation; and which will require a minimum of attention in use.

A further object of the invention is to generally improve andsimplify-various details of the propelling means for the time train, bywhich the cost of manufacture may be materially reduced.

A further object and advantage is to provide improved means for mountingthe va-, rious parts in an attractive and convenient manner and forsimplifying the various electrical connections.

Various other objects and advantages will be apparent from the followingdescription of an embodiment of the invention, and the novel featureswill be particularly pointed out hereinafter in connection with theappended claims.

In the accompanying drawings:

Fig. 1 is a front elevation of a clock constructed in accordance withthis invention;

Fig. 2 is a sectional elevation of the same,

the section bein taken a roximatel -alon the line 22 of Fig. 5; pp y gFig. 3 is a sectional elevation of the same, W1th the section takenapproximately along the line 33 of Fig. 5;

Fig. 4 is a perspective of the crutch and driving pawl of the same;

Fig. 5 is a sectional elevation of the'same from front to rear, thesection being taken approximately along the line 5-5 of Fig. 2;

Fig. 6 is a sectional elevation of a portion of the same, as viewed fromthe rear and approximately along the line 6-6 of Fig. 5

Fig. 7 is a reverse of the impulse element and various parts forresetting the same and illustrating the relative position of a number ofparts at one point of the cycle of operation of the clock;

Fig. 8 is an elevation of the contact mechanism of the same;

Fig. 9 is a sectional plan of a portion of the clock, the section beingtaken approximately along the line 9-9 of Fig. 5;

Fig. 10 is a sectional elevation somewhat similar to Fig. 3, butillustrating the pendulum in a different position, and illustrating thenormal operation of the clock when the pendulum has its full swing;

Fig. 11 is a sectional elevation of a part of the mechanism shown inFig. ,10, and illustrating an intermediate step in the tripping orrelease of the impulse member when the amplitude of oscillation of thependulum falls below a desired amount;

Fig. 12 is an elevation somewhat similar to Fig. 11, but illustratingthe position of parts an instant after the impulse member has beentripped;

Fig. 13 illustrates the impulse element acting upon the pendulum;

Fig. 14 is a diagram of the electrical connections of the clock;

Fig. 15 is a perspective of the latch releasing lever;

Fig. 16 is a perspective of the trip lever which operates upon the levershown in Fig. 15;

Fig. 17 is a sectional elevation illustrating the operation of the levershown in Fig. 15 upon the latch which obstructs movement of the impulseelement, the section being taken approxin'iately along the line 17-17 ofFig. 21

Fig. 18 is a sectional elevation through the mechanism for driving theratchet wheel and preventing reverse movement of thetime train, thesection being taken approximately along the line 18l8 of Fig. 5;

Fig. 19 is a similar elevation, but with the parts in a differentoperative relation to one another;

Fig. 20 is a sectional plan of the same, with the section takenapproximately along the line 20 of Fig. 5;

Fig. 21 is an elevation of the. armature and its mounting; and

Fig. 22 is a sectional plan of the mag.- nets and support, the sectionbeing taken approximately along the line 22 22 of Fig. 5.

In the illustrated embodiment of the invention, the mechanism may besupported upon any suitable base 1 and enclosed by an invertedtransparent hell 2. A cylindrical tubular standard or shell 3 (Figs. 5,6, 9 and 22) is received at one end in an opening 4 of the base 1, itsmovement through the opening at being limited by the rib or corrugation5 provided peripherally in the standard a short distance from its lowerend, as shown in Fig. 6. The lower end of the tube or standard 3 isflanged inwardly as at 6, so as to confine therein a plate 7. A plate 8fits over the lower end of the opening 4, and one or more screws 9 arepassed through the plate 8 and threaded into the plate 7 so as to holdthe tube or standard within the opening 4 and extending upright from thebase 1. A battery unit 10, such as one of the dry cell type, is mountedwithin the tube or standard 3, with an end contact terminal 11 uppermosttherein, as shown in Fig. 5. A cap 12 fits the upper open end of thetube 3 and holds the battery unit there within and compressed against aspring 13 disposed in the bottom of the standard and between the batteryunit and the plate 7. The spring 13 grounds the other battery unitterminal to the tube 3 through plate 7.

The cap 12 is preferably made of molded insulating material and isprovided with a projecting finger 14 from its under face which isadapted to hook into an aperture 15 in the tube 3 adjacent one end ofthe latter, so as to corfine the cap 12 releasably at one edge to thetube 3. The cap is provided with a conducting strip 16 which may beimbedded therein, this strip extending from a side edge of the cap intothe cap and then outwardly through the interior of the lower face of thecap, so as to form a spring contact finger 17 which presses, preferablyyieldingly, against the terminal 11 of the battery unit and forms anelectrical connection therewith. The outer end of the strip 16 may beprovided with a latch hump 18 over which may be releasably hooked orlatched an end of a contact spring or member 19, the contact springbeing mounted so that its free end will normally be snapped over thehump 18 and hold the cap 12 upon the tube 3. The contact linger 15),however; may he sprung latorally to release the hump 1S and permitremoval of the cap when a battery is to be inserted or removed.

A pair of electromagnets 20 and 21 are disposed on opposite sides of thetube 3, intermediate the height of the tube and so as to extendsubstantially parallel to one another and transversely of the axis ofthe tube. The cores at corresponding ends of the magnets areconnected toa cross bar 22 which extends crosswise of the tube 3 at one sidethereof, the bar 22 being of magnetic material or material having largepermeability. A strap 23 extends partially around the tube 3 on the sideopposite the bar 22, and at its ends is connected to the bar 22 in anysuitable manner, such as by screw bolts 24 passing through the bar 22and through bent angular ends 25 of the strap 23 and carrying nuts '26upon the projecting ends. A filler block 27 is disposed between the bar22 and the adjacent side of the tube 3, so that when the bolts 24 aretightened against the tube, the strap will rigidly clamp theelectromagnets to the tube.

The filler block 27 may be of any suitable construction, but preferablyit is made of a channel of sheet material disposed with its bottomportion or wall flat against a face of the bar 22 and with its sidesextending edgewise into contact with the periphery of the tube 3. Thesides or arms of the channel are cut or notched arcuately so as toreceive into them the periphery of the tube 3 and fit closely againstthe same throughout their length. Such a channel may be easily formed bystamping a flat blank with two opposite edges curved in accordance withthe curvature of the periphery of the tube 3, and then bent into theform of a channel with the notched sides of the blank forming the sidesof the channel.

A time train 28 (Fig. 5) of any suitable construction is mounted on aclock frame 29 formed of spaced plates in the rear of a dial plate 30,and carries the usual hour hand 31 and minute hand 32 in front of thedial plate. A gear 32 is mounted on the minute hand shaft 33 and isfrictionally clamped against a shoulder on that shaft by a compressionspring 34, as usual in clock mechanisms. The gear 32 is driven by pinion35, and the latter is driven by a reduction train of gears 36 from aratchet wheel 37 Figs. 3, 10, 18, 19 and 20). An arm 38 (Fig. 5) extends from the upper end of the tube 3 to the upper edge of the forwardplate of the frame 29, being connected to a rearwardly turned ear 39thereof in any suitable manner such as by a screw 40. A springsuspension element 41 is secured to and depends from the arm 38, in therear of the clock mechanism and the clock frame formed by the plates 29,and at its lower end carries pendulum supporting pins 42 projecting fromopposite faces therefrom and in alinement with one another. A pendulum43 is hooked over the pins 42, so as to oscillate from side to side ofthe clock as permitted by the fiexure of the suspension element 41.

A pendulum crutch 44 (Figs. 4 and 5) is fixed upon a shaft 45 which isrotatably mounted in the clock frame, so as to depend just in front ofthe pendulum, and carries a forked'lateral extension 46 which embracesthe pendulum 43, so that the pendulum and crutch will oscillate inunison. The crutch is provided intermediate of its ends with an arm 47(Fig. 3), which extends in its plane, then laterally therefrom and thenparallel to its first section, and the free end of this arm and thecrutch body together serve to rotatably support the ends of a shaft 48(see also Fig. 20). The portion of the shaft 48 between the arm 47 andthe body of the crutch 44 is larger than its ends, which are mounted inthe crutch and its arm, and at one side thereof is provided with atransversely extending groove 49 (Fig. 20).

A driving pawl 50, which may be formed of a strip of stamped or rolledsheet metal, is provided intermediate of its ends with a notched portion51 which is fitted into the groove 49 of the shaft, and the material ofthe shaft immediately along the groove 49 1S upset somewhat over theouter face of the strip so as to rigidly confine the strip 50 to theshaft 48. One end of the strip 50' engages with the arm 47 to limit themovement of the strip in one direction, and the other end 52 of thestrip 50 is bent or formed angularly so as to make the strip L-shaped.This free, angular end 52 of the strip extends into proximity to theratchet wheel 37 and co-acts with the teeth thereof, to drive the same.Thus the pawl formed by the strip 50 and pivotally mounted on the crutchWhlCll oscillates with the pendulum serves to propel the ratchet wheelby increments corresponding to the oscillations of the pendulum. Thusthe pendulum directly transmits 1ncrements of movement to the timetrain.

A shaft 53 (Figs. 18 and 19) is rotatably mounted in the clock frame 29and mounts a strip 54 (Figs. 18 and 19) of sheet metal in a side thereofin the same manner as described for the mounting of the strip 50 in theshaft 48. One end of the strip 54 extends into engagement with theratchet wheel teeth in a manner to prevent movement thereof in adirection reverse to that imparted by the driving pawl 50 on thependulum crutch, the strip 54 then extending angularly as at 55 to serveas a weight urging that end of the strip 54 into yielding engagementwith the teeth of the ratchet wheel. The other end of the strip 54 isengageable with a stud 56 of the clock frame to limit movement of thepawl formed by the strip 54 toward the ratchet wheel, thereby permittingmovement of the pawl into engagement with the teeth of the ratchet wheelwhile limiting such movement before the pawl reaches the bottoms of thetooth spaces. One of the shafts 57 (Fig. 5) of the time train extendsforwardly through the dial plate 30 and removably and frictionallycarries a second hand 58 for indicating the seconds.

The means for keeping the pendulum in motion and thereby causing acontinued operation of the time train will next be described. For thispurpose an impulse element 59, which may be in the nature of a gravityarm or lever, is mounted in the clock frame 29 and normally in anapproximately horizontal position. The gravity arm may be formed bystamping it from sheet metal, with one end bent angularly thereon-so asto form therewith a U, through the arms of which passes a shaft 60 whichis mounted in the clock frame 29 and serves as a pivotal mounting forthe impulse element or gravity arm.

A small arm 61 extends from the upper edge of the arm or element 59 andis bent over into parallel and spaced relation to a face of the arm 59.An impulse roller 62 is rotatably mounted between the free end of thesmall arm 61 and the body of the arm 59. Vhen the impulse element orarm.59 is released and falls by gravity, the roller 62 engages with animpulse pin 63 carried by the crutch 44 at one side of its axis, and byits pressure thereon causes a swinging movement of the crutch in thedirection of the latters oscillation. Inasmuch as the crutch isconnected at its forked end, to the pendulum, the falling arm or weight59 acts to propel the crutch 44 and pendulum 43 in a direction ofoscillation of the latter, thereby increasing the amplitude ofoscillation of the pendulum.

An armature element 64 is provided with oppositely extending bearingstuds 65, which are rotatably mounted in the clock frame with the endsof the armature element movable into andout of alinement with the freeends of the cores of the electromagnets 20 and 21. Thus when theelectromagnets are energized, the armature will be rocked about itsbearing studs from the position shown in Figs. 3 and 10, for example,into the position shown in Fig. 7, that is, in a direction to reduce theair gap between the ends of the armature and the free ends of theelectromagnets.

The armature element may be formed of a series of parallel plates spacedapart by suitable studs 66, Fig. 7, and the two outer plates havedepending arms 67 which support between them a bearing shaft 68. A

bell crank lever 69 is pivotally mounted on the shaft 68, and one end ofthis bell crank has a latch nose 70 which is engageable with an car 71extending laterally from a depending branch 72 of the impulse element orarm 59. A tension spring 73 is connected between a laterally extendingcar 74 on the bell crank (39 and an ear 7:) on one of the arms 67, so asto urge the bell crank (39 in a direction to latch the nose 7() beneaththe car 71.

One of the plates of the armature element is provided with a pair ofcars 76 (Figs. 2 and 21) on opposite sides of the axis of the bearingstuds (55. and these ears extend through areuate slots 77 in one of theplates in the clock frame 29. A tension spring 78 is connected to eachcar 76 of the armature and also to suitable ears struck out of one ofthe plates of the clock frame 29, so as to yield ingly urge or bias thearmature into a retracted position such as shown in Figs. 2, 3 and 10,and when the armature is so retracted, it acts through the bell cranklatch (39 to hold the impulse element or gravity element 59 poised, withthe impulse roller (32 above and out of the path of oscillation of theimpulse pin 63.

A strap 7 9 is fitted over that bearing stud (35 which extends throughand has a bearing in that plate of the clock frame 29 through which theears 76 of the armature extend and a spring 80 is connected at one endto the free ends of this strap and at its other end 15 anchored, withthe spring under tension, to a suitable part of the clock frame 29, sothat the spring strap will exert a frictional action on that stud 65 ofthe armature element and tend to snub minor oscillations or rebounds ofthe armature element under the action of the retracting spring 78 or abuffer to be described hereinafter. One arm of the bell crank latch 69is bent angularly as at 81. which bears upon a lever 82 also pivoted atone end upon the shaft 68.

The spring 73 tends to rock the latch lever or bell crank 69 in adirection to force the lever 82 in one direction and move the lever 82in one direction, and movement of the lever 82 in that direction islimited by the engagement of the free end of the lever 82 with a pin 83projecting from another lever 84. The lever 84 at one end is bent intothe form of a U, the arms of which are pivotally mounted upon a shaft 85carried by the clock frame 29, and downward movement of the lever 84 islimited by its engagement with an ear 86 (Fig. 18) of the clock frame.The lever 84 normally rests upon the car 86, and the lever 82 bearsagainst the pin 83 which in turn limits the movement of the bell cranklatch 69 beyond its latching position shown in Fig. 10.

A dog 87 (Figs. 10 to 13) is pivoted to the free end of the lever 84 soas to depend therefrom and oscillate freely thereon in a plane parallelto the oscillation of the pendulum. The lower or free end of this dog-87is provided with two spaced apart pointed ends 88 and 89, Fig. 10, bothpoints being beveled upon both faces, and the point 88 being the longerof the two. These pointed teeth 88 and 89 include between them a notch90 (Fig. 13) which cooperates with a knife edge of a lug 91 carried byan arm 92 on the crutch 44 (see Fig. 4), the action between the dog 87and the knife edge of the lug 91 constituting what is known in this artas a Hipp con-- tact.

As the crutch oscillates back and forth, the lug 91 will rock the dog 87idly back and forth so long as the lug 91 passes sutiiciently beyond thedog to clear it and permit descent of the dog 87 before the lug 91returns in the oscillation or swing in the reverse direction. The dog 87is hung at such a point relative to the oscillation of the lug 91 thatwhen the pendulum exceeds a certain minimum amplitude of oscillation,the lug 91 will clear the dog, but when the amplitude drops below thisll'lllllllllll'l'l, the lug 91 will not clear the notched end of the dog87, but will merely pass the shorter point 89 in the free end of thesame, such condition being shown in Fig. 11. T hereupon when thependulum starts in the reverse direction, the lug 91 and the dog 87 willhave a toggle like action with one another and cause a raising of thelever 84.

As the lever 84 rises, its pin 83 will engage with the free end of thelever 82 and rock the same in a direction to rock the bell crank latch69 out of latching engagement with the impulse element or gravity arm59, whereupon the latter falls and its impulse roller 62 delivers adriving impulse to the impulse pin 63, and through the crutch 44 to thependulum, thus increasing the amplitude or swing of the pendulum beyondthe selected minimum.

By having the point 88 of the dog 87 longer than the other point 89, theknife edge of the lug 91 will only engage in the notch 90 when passingthereby in one direction. That is, when the knife edge engages thelonger point first and then passes over it, it will clear the shorterpoint and not cause a release of the impulse element. The longer pointis so positioned as to cause a release of the impulse element only atthe beginning of in its free end through which the contact tip 95loosely projects, so as to permit direct engagement of the tip 95 by thescrew at the end of the impulse movement of the element or arm 59. Theleaf spring 96 is normally urged against the under face of the bracketso 'as to project the tip 95 as far as possible through the opening 98.

The spring 96 and bracket 97 are secured to one of the plates of theclock frame by a screw 99 which is insulated from the plate of the frame29 by a flanged insulating bushing 100 and an insulating washer 101which surround the shank of the screw 99 where it passes through theplate of the clock frame, and abut against both faces of the plateadjacent the opening through which the screw 99 passes. The screw mayhave a nut 102 and a washer 103 by which the parts may be firmly clampedtogether and to the plate of the clock frame. An electrical connector104 may be interposed between the bushing 100 and a face of the bracket97 so as to be clamped between the same and make an electrical contactwith the bracket and also with the spring 96. A wire 105 connects theconnector 104 with one end of one of the electromagnets, such as21. Thebracket 97, contact tip 95 and spring 96 together serve as a contactmember which not only stops or limits the impulse movement of saidimpulse element, but also makes an electrical connection between theimpulse element and the electromagnet 21. The purpose of the electricalconnection will appear shortly.

The combination contact spring andlatch member 19 which is mounted byscrews 24 upon the connecting magnetic bar 22 may be T-shaped with theleg or tail of the T forming the free spring contact or latch engagingwith the hump 18 on the cap 12 (Fig. 5), and with a head of the Textending along the upper edge of the bar 22 and secured at its ends tothe bar 22 by the screws 24. A conducting strip 106 (Figs. 5 and 6) isdisposed along the lower edge of the bar 22 and secured thereto byanother pair of the screws 24. The contact spring and latch member 19and the strip 106 are insulated from the screws 24 and from the bar 22by suitable bushings and washers 107, so that the member 19 and strip106 will be electrically separate from one another and from the bar 22.One end of the head of the T of member 19 may be connected by a wire 108to one terminal of one of the magnets, such as 20 (Figs. 5, 6 and 9),the other terminal of the magnet being connected by a wire 109 to oneend of the conducting strip 106. The other end of strip 106 may beconnected by a wire 110 to one terminal of the electromagnet 21, theother end or terminal of the magnet 21 being connected as beforeexplained by wire 105 to the contact member 97.

One end of the battery unit 10 is grounded to the tube 3 and through itto the clock frame 29 which mounts the impulse arm 59, so that when theimpulse element orarm 59 falls and ltsscrew 94 engages with the contacttip 95, a circuit will be closed as follows: From the terminal 11 of thebattery unit 10 through contact finger 17, conducting strip 16, latchhump 18, contact member 19, wire 108, electromagnet 20, wire 109, strip106, wire 110, electromagnet 21, wire 105, contact bracket 97, contacttip 95, contact screw 94, impulse element 59, clock frame 29, back tothe tube 3, to which is grounded the other end of the battery unit 10.To prevent oil in the bearings of the pivot of the arm 59 preventing agood ground contact between the arm 59 and the remainder of the clockframe, a flexible wire 111 (Figs. 10 and 15) is soldered at one end tothe arm 59 near its pivotal support, and at its other end to a suitablepart of the clock frame 29.

When the circuit just described is closed, the electromagnets will beenergized and will attract the armature element 64 from the retractedposition shown in Figs. 3 and 10 against the action of springs 78, intothe position shown in Fig. 7. At the time that the impulse element 59was released by the disengagement of latch nose 7 0 from the ear 71 ofthe element 59 (Fig. 7) the ear 71 fell or moved with the element 59 inthe direction in which the armature would move when attracted, andtherefore as the armature closely approaches the attracted positionshown in Fig. 7, the latch nose of the bell crank latch 69 will snappast the ear 71 and therefore into latched engagement with the impulseelement 59. This relatching of the bell crank 69 to the impulse elementoccurs as the armature is approaching its attracted position shown in Fi7, and just prior to the completion of this relatching of the bell crankto the impulse arm, the armature element engages with a resilient buffer112 in the form of a leaf spring secured to the clock frame.

Since the armature element has considerable inertia while moving intoattracted position, it will continue to move in the same directionagainst the action of the buffer 112 for some distance sufficient toeffect a relatching thereof to the element 59, and then it will be givena rebound movement by the buffer 112. This rebound is of sufiicientextent to partially return the armature element and through it partiallyreturn the impulse element to which it has been relatched, this returnbeing sufficient to carry the contact screw 94 out of contact with thecontact member against which it had struck and by which it had beenstopped. This opens the circuit of the electromagnets, and the resultingdeenergization of the electromagnets permits a complete return of thearmature element to retracted position under the influence of springs78. The armature element in returning, of course elevates or resets theimpulse element in poised or inoperative position, ready for release andreactuation of the pendulum. The friction of the plate 79 on a bearingstud of the armature element snubs the minor oscillations of thearmature element at the ends of its limits of movement, so that therewill be no danger of an immediate remaking of the circuit by the contactscrew, 94 and contact tip 95.

In the operation of an electric clock constructed in the mannerhereinabove described and illustrated, the pendulum when set inoscillation drives the ratchet wheel 37 and through it drives the timetrain. At this time the impulse element 59 is in its raised or poisedposition and latched in that position by the bell crank 69 carried bythe armature element 64, which is in turn held in My tracted position bythe springs 78 because the electrical circuit through the elcctromagnetsis at this time broken by the separation of the contact screw 94 andcontact tip 95. hen the amplitude of oscillation of the pendulumdecreases below a selected minimum, that is a minimum below which theratchet wheel will not be given the desired increments of uioven'eut at.each swing of the pendulum. the knife edge of the lug 91 fails tocompletely pass the depending dog 87 and passes only the shorter point89, which position of the parts is shown in Fig. 11 at one end of theswing of the pendulum in its shorter are.

As the pendulum starts to swing in the reverse direction, the lug 91engaging in the notch 90 acts to elevate the dog 87 and through it thelever 84, and the latter through its pin 83, which is elevatedtherewith. rocks the release lever 82 which in turn rocks the bell crank69 out of latching engagement with the car 71 of the impulse element 59.This approximate condition of parts is shown in Fig. 12. Thereupon theimpulse element 59 falls under the influence of gravity, and its impulseroller 62 engages with the impulse pin 63 of the crutch as shown in Fig.13. The pressure of the roller 62 upon the pin 63 tends to force thecrutch 44 and the pendulum 43 more rapidly in the swing or oscillationjust started, with the result that the amplitude of the pendulum 43 isvery materially increased by the pressure from the impulse elementbefore the contact screw 94 reaches and is stopped by the contact tip95.

Immediately upon the closing of the circuit and the stopping of theimpulse element or actuator 59, the armature element is attracted intothe position shown in Fig. 7 and relatched to the impulse element, therebound 3 caused by the buffer 112 causing a return of these partssufficient to open the circuit by a separation of the contact screw 94and contact 'tip 95. whereupon the springs 78 return the armatureelement to retracted position and elevate the impulse element 59 intoits poised or inoperative position ready for a new release and a newactuation of the pendulum when the amplitude of oscillation of thelatter again falls to the selected minimum. By

adjusting the contact screw 94 through the forked arms 93 of the impulseelement the instant at which the impulse element is stopped and thecircuit closed may be varied within limitations, so that the instant ofrelatching of the armature element to the impulse element may be variedsufficiently to insure an opening of the circuit by partial return ofthe impulse element during the rebound caused by the buffer 112.

In order to insure opening of the circuit of the electromagnets at theend of the armature stroke, I may provide a leaf spring 113- (Figs. 3,7, 10 and 13) which is rigidly secured at one end to the cross arm 113(Fig. 7) of the U-shaped bearing end of the impulse element, arm orlever 59, and bears yieldingly against an ear 114 projecting from thelower edge of the arm or lever 59, so as to position the free end of thespring in a position to be engaged by an arm 64 of the armature 64, justprior to the completion of the attraction stroke of the armature. Thearm 64 will elevate and flex the spring 113 as the armature completesits movement into attracted position", and the spring 113 willyieldingly elevate the arm 59 sufiicient'ly to break the circuit at thescrew 94 and tip 95. Upon the breaking of the circuit followingseparation of the screw 94 and tip 95, the armature is retractedsufficiently to engage and directly elevate the arm 59 before the lattercan fall when the armature releases the spring 113 thus preventingimmediate reclosing of the circuit. To this extent either the bufferspring 112 or spring 113 may be dispensed with, without making thedevice inoperative, but the use of both gives greater insurance of anopening of the circuit, and greater smoothness of action, and lessnoise.

In order to cushion the armature element as it reaches retractedposition and thus minimize the noise caused by the operation of theclock I may also provide a leaf spring 115 mounted at one end upon abracket lit; and bearing at its free end upon the armature when thelatter is in retracted position and yieldingly urging the armatureelen'ient toward attracted position against. the action of the springs78. The spring 115, however, is weaker than the springs 78. so that nomaterial return movement of the armature element results. but at thesame time the spring 115 cushions the return of the armature elementinto retracted position.

It will be noted. Figs. 2 and 5, that the minute hand shaft is mountedin an ear or tongue 117 which is struck out from the forward plate ofthe clock frame 29 and offset forwardly thereof so as to mount the hourhand drive pinion 118 fixedly thereon and in a plane forwardly of tl1 eforward plate of the frame 29. A part of the pinion may lie in theopening 118 formed in the frame by the striking out of the tongue or car117. The gear 32 may be frictionally pressed against a boss or hub ofthe pinion 118 by the spring 34 as explained hereinbefore. The minutehand shaft maybe mounted at its rear end in another plate of the frame29. An hour hand sleeve or cannon pinion 119 is rotatably mounted on theforward end of the minute hand shaft in front of the tongue or ear 117,and the cannon pinion and pinion 118 both mesh with a. combinationpinion and gear 120 which is mounted by a stud upon the forward face ofthe forward plate of the frame :29. To remove the minute hand shaft 32it is merely necessary to remove the frame plate from the rear end ofthe shaft, remove the minute hand, hour hand and cannon pinion, and thendraw the shaft rearwardly out of the ear or tongue 117 without removalof the pinion 118 from the shaft 32, as has heretofore always beennecessary. The pinion 118 is commonly secured to the shaft 39 by a drivefit and after it has been removed a few times it fails to fit tightlyand often becomes loose in use with resulting irregularities in the timekeeping of the clock or watch.

With this construction however it is never,

necessary to remove the pinion 118 in disassembling the clock andtherefore it never becomes loose.

Inasmuch as the pendulum swings at a uniform rate within a considerablerange of an'iplitude, the time train will be driven at a uniform rateregardless of the weight or propelling force of the impulse element.which merely increases the amplitude of swing of the pendulumsufliciently to keep the pendulum swinging within the range ofamplitudes at which its period is substantially constant. Consequently.a clock constructed in accordance with this invention will keepexceptionally accurate time beca use the time. will not vary with theunwinding of a spring, and inasmuch as the amount of current utilized isrelatively small, a relatively small battery unit will operate the clockfor a very considerable length of time without attention. A clockconstructed in this manner also presents an attractive appearance owingto the fact that the battery unit is concealed in the tube 3. and theworks of the clock are exposed to view.

It will be obvious that various changes in the details which have beenherein described and illustrated in order to explain the nature of theinvention. may be made by those skilled in the art within the principleand scope of the invention as expressed in the appended claims.

I claim as my invention 1. In an electric clock, an oscillating element,a propulsion element operable on said oscillating element to impartimpulses to the latter, a magnetic element including a movable part, alatch carried by said part and having latched engagement with saidpropulsion element to hold the latter in poised position where it isinoperable upon said oscillating element, resilient means normallyholding said movable part in retracted position with its latch holdingthe propulsion element in said poised position, means operableautomatically when the amplitude of the producing a movement of saidmovable part in a direction to carry its latch into latching engagementwith said propulsion element, a resilient buffer engaged by said part.when the latter moves under the influence of the closed circuit. justprior to the relatching of the latch to said propulsion element, wherebysaid part will be given a rebound at the end of its movement underattraction and after said latch has been relatched to said propulsionelement. the rebound being sufficient to return said propulsion elementsufficiently to open the circuit which it closed when propelling saidoscillating element, and permit retraction of said part by saidresilient means and a complete return of said propulsion element topoised position.

2. In an electric clock. an oscillating element. a propulsion elementoperable on said oscillating element to impart impulses to the latter, amagnetic element including a movable part, a latch carried by said partand having latched engagement with said propulsion element to hold thelatter in poised position where it is inoperable upon said oscillatingelement. resilient means normally holding said movable part in retractedposition with its latch holding the propulsion e ement in said poisedposition, means operable automatically when the amplitude of theoscillating element falls below a selected minimum for operating saidlatch to release the propulsion element at approximately the beginningof an oscillation of said oscillating element, a contact member disposedfor engagement by and limiting movement of said propulsion element whenthe latter is released and imparts an impulse to said oscillatingelement, an electrical circuit including said magnetic and propulsionelements and contact member, for moving said movable part in a directionto carry its latch into latching engagement with said propulsionelement, a resilient buffer engaged by said part, just prior to therelatching of the latch to said propulsion element, whereby said partwill be given a rebound at the end of its movement under attraction andafter said latch has been relatehed to said propulsion element. therebound being sufficient to return said propulsion element sufiicientlyto open the circuit which it closed when propelling said oscillatingelement, and permit retraction of said part by said resilient means anda complete return of said propulsion element to poised position, saidpropulsion element and contact member having relatively adjustablecontact portions whereby the limit of travel of the propulsion elementin a propelling direction and the point at which relatching occursbetween said propulsion element and said part may be varied.

3. In an electric clock, an oscillating element, a biased propulsionelement operable when released to drive said oscillating element in onedirection, a circuit closed by said propulsion element and including amagnetic device with a movable part operated in one direction when saidcircuit is closed, means for urging said part to retracted position whensaid circuit is open, a latch carried by said part and holding saidpropulsion element in poised inactive position when said part isretracted, means operable automatically, when the amplitude ofoscillation of the oscillating element decreases below a selectedamount, for unlatching said propulsion element, a resilient bufferengaged by said part as it approaches the end of its movement underattraction caused by the closed circuit and prior to its relatchingengagement with said propulsion element, so as to cause a rebound ofsaid part, and a resetting of the propulsion element sufliciently toopen the circuit and permit a return of said part and propulsion elementto retracted and poised posit-ions respectively.

4. In an electric clock, an oscillating driver element, an impulseelement operable upon said driver element to increase its amplitude ofoscillation, means for holding said impulse element in poisedinoperative position, means operable automatically upon said holdingmeans, when the amplitude of oscillation of said driver elementdecreases below a selected value, for causing a release of said impulseelement, said-holding means including a magnetically responsive part,yieldingly biased to retracted and holding position, means inchuL ing anelectric circuit closed by said impulse element at the end of itsmovement when released for causing an attraction of said part intoreengagement with said impulse element, and a resilient bufferengageable by said part just prior to the end of its reengagement withthe impulse element, whereby the rebound caused thereby will return saidimpulse element sufliciently to cause an opening of said circuit and amagnetic release of sai part.

5. In an electric clock, an impulse element biased for movement in onedirection, an oscillating element impelled thereby by its movement insaid one direction means for releasing said impulse element when theamplitude of oscillations of said oscillating ele ment decreases below adesired value, a magnetic device having a movable magneticallyresponsive part biased to retracted position and releasably engageablewith said impulse element to hold it inoperative when in retractedposition, an electric circuit including said device closeable by theimpulse element at the end of its driving action, to cause an attractionof said part to reengage said impulse element, and means for causing arebound of said part immediately after its reengageinent with saidimpulse element, the extent of rebound being suflicient to move theengaged impulse element in a return direction and cause an opening ofsaid circuit permitting retraction of said part and resetting of saidimpulse member.

6. Inan electric clock, an impulse element biased for movement in onedirection, a magnetic device having a movable magnetically responsivepart biased to retracted position and releasably holding said elementagainst movement in said one direction, an electric circuit includingsaid device and controlled by said element whereby at the end ofmovement of said element in said one direction a movement of said partto reengage said element will be caused, and means engageable by saidpart at approximately the end of the Fast mentioned movement for causinga rebound of said part just after its reengagement with said elementwhereby said element will be returned toward initial poised posi tionsufliciently to restore said circuit to its original condition, permitretraction of said part, and complete return to initial poised positionof said element by said part.

7. In an electric clock, an impulse element biased for movement in onedirection, a mag netic device having a movable magnetically responsivepart biased to retracted position and releasably holding said elementagainst movement in said one direction, an electric circuit includingsaid device and controlled by said element whereby at the end ofmovement of said element in said one direction a movement of said partto reengage said element will be caused, means engageable by said partat approximately the end of the last mentioned movement for causing arebound of said part just after its reengagement with said elementwhereby said element will be returned toward initial poised positionsufliciently to restore said circuit to its original condition, permitretraction of said part, and complete return to initial poised positionof said element by said part, and means for snubbing minor movements ofsaid part.

8. In an electric clock, an impulse element biased for movement in onedirection, a magnetic device having a movable magnetically responsivepart biased to retracted position and releasably holding said elementagainst movement in said one direction, an electric circuit includingsaid device and controlled by said element whereby at the end ofmovement of said element in said one direction, a movement of said partto reengage said element will be caused, means enga eable by said partat approximately the end 0 the last mentioned movement for causing arebound of said part just after its reengagement with said elementwhereby said element will be re-.

' turned toward initial poised position suiii ciently to restore saidcircuit to its orignal condition, permit retraction of said part, andcomplete return to initialpoised position of said element by said part,and a frictional device acting upon said part for snubbing its minormovements.

9. In an electric clock, an impulse element biased for movement in onedirection and having a contact member adjustably projecting therefrom insaid one direction, a magnetic device having a movable magneticallyresponsive part biased to retracted position and releasably holding saidelement against movement in said one direction, a contact memberdisposed in the path of said impulse member when the latter is released,whereby the impulse movement of said element will be limited by theengagement of its contact member with said second contact member, theadjustment of said first member varying the extent of movement of saidsecond impulse element, and an electric circuit including said contactmembers and said device, whereby when the circuit is closed byengagement of said contact members, said part will be magneticallyshifted into reengagement with said element, and means engageable bysaid part at approximately the end of its movement following the closureof said circuit for causing a rebound of said part immediately after itsreengagement with said element, whereby said element will be returnedtoward initial poised position during such rebound, sufliciently to opensaid circuit and permit retraction of said part and also a completereturn to initial poised position of said element by,

said part.

10. In an electric clock, an impulse element biased for movement in onedirection, a magnetic device having a movable magnetically responsivepart biased to retracted position and releasably holding said elementagainst movement in said one direction, said element having a contactprojection, an abutment, a

contact element resiliently pressed against p said abutment and having acontact section within the path of said projection on said elementwhereby the movement of said element' in one direction will beresiliently checked by the engagement of said projection with saidcontact member, the engagement of the contact member with said abutmentlimiting the movement of said contact member toward said projection, anelectric circuit including said element, said contact member, and saiddevice, whereby at the end of movement of said element in said onedirection said circuit will be closed, and said part moved by magneticattraction in one direction to reengage said element, and a bufferengageable by said part at approximately the end of its movement underattraction for causing a rebound of said part immediately after itsreengagement with said element, whereby said element will be returnedtoward initial poised position sufficiently to open said,

element against movement in said one direction, an electric circuitincluding said contact member and said device and closed by engagementof said screw and contact member to cause a movement of said part in adirection to reengage said element, and means operable by said part atapproximately the end of its movement following the closing of saidcircuit for causing a rebound of said part immediately after itsreengagement with said element, whereby said element will be returned bysaid part toward initial poised position sufficiently to open thecircuit and permit complete return of said element by said part, saidcontact member being resiliently held in contact position andresiliently opposing movement thereof by contact thereagainst. of saidcontact screw.

12. In an electric clock, an oscillating element, an impulse elementbiased for movement in a direction to engage said oscillating elementand increase its amplitude of oscillation, an electromagnet having amovable part, means for yieldingly operating said part in one directionwhensaid electromagnet is dcenergized. a latch element carried by saidpart and engaging with said impulse element to hold it in poisedinoperative position while said part 1s in retracted position, meansoperable upon said latch to release said impulse element when theamlitude of oscillation of said oscillating element falls below aselected minimum, contact members operable to check movement of saidimpulse element when released, a circuit including said electromagnetand controlled by said contact members, whereby when said impulseelement is checked by said members said movable part will be shifted ina direction to carry its latch into relatched engagement with saidimpulse element, a resilient bufi'er engaged by said part at the end ofits relatching movement for causing a rebound of said part afterrelatching of said part to said impulse element, of an extent sulficientto separate said contact members and permit a complete return of saidpartand impulse element to initial position.

13. In an electric clock, an oscillating element, an impulse elementbiased for movement in a direction to engage said oscillating elementand increase its amplitude of oscillation, an electromagnet having amovable part, means for yieldingly operating said part in one directonwhen said electromagnet is deenergized, a latch element carried by saidpart and engaging with said impulse element to hold it in poisedinoperative position while said part is in retracted position, meansoperable upon said latch to release said im ulse element while theamplitude of oscil ation of said oscillating element falls below aselected minimum, contact members operable to check movement of saidimpulse element when released, a circuit including said electromagnetand controlled by said contact members, whereby when said impulseelement is checked by said members said movable part will be shifted ina direction to carry its latch into relatched engagement with saidimpulse element, a resilient buffer engaged by said part at the end ofits relatching movement for causing a rebound of said part afterrelatching of said part to said impulse element of an extent sufficientto separate said contact members and permit a complete return of saidpart and impulse element to intial position, one of said contact membersbeing carried by said impulse element and the other bein mounted in aposition to be engaged thereby at the end of the impulse movement ofsaid impulse element.

14. In an electric clock, an oscillating element, an impulse elementbiased for move ment in a direction to engage said oscillating elementand increase its amplitude of oscillation, an electromagnet having amovable part, means for yieldingly operating said part in one directionwhen said electromagnet is deenergized, a latch element carried b saidpart and engaging with said impulse e ement to hold it in poisedinoperative position while said part is in retracted'position, meansoperable upon said latch to release said impulse element when theamplitude of oscillatlon of said oscillating element falls below aselected minimum, contact members operable to check movement of saidimpulse element when released, a circuit including said ment to initialelectromagnet and controlled by said con tact members, whereby when saidimpulse element is checked by said members said movable part will beshifted in a direction to carry its latch into relatched engagement withsaid impulse element, a resilient buffer engaged by said part at the endof its relatching movement for causing a rebound of said part afterrelatching of said part to said impulse element, of an extent sufficientto sep arate said contact members and permit a complete return of saidpart and impulse element to initial position, one of said contactmembers being carried by said impulse element and the other bein mountedin a position to be engaged thereby at the end of the impulse movementof said impulse element, one of said contact members being adjustabletoward and from the other so as to vary the extent of movement of saidimpulse element before engagement of said members.

15. In an electric clock, an oscillating element, an impulse elementbiased for movement in a direction to engage said oscillating elementand increase its amplitude of oscillation, an electromagnet having amovable part, means for yieldingly operating said part in one directionwhen said electromagnet isdeenergized, a latch element carried by saidpart and engaging with 'said impulse element to hold it in poisedinoperative position while said part is in retracted position, meansoperable upon said latch to release said impulse element when theamplitude of oscillation of said oscillating element falls below aselected minimum, contact members operable to check movement of saidimpulse element when released, a circuit including said electromagnetand controlled by said contact members, whereby when said impulseelement is checked by said members said movable part will be shifted ina direction to carry its latch into relatched engagement with saidimpulse element, a resilient bufler engaged by said part at the end ofits relatching movement for causing a rebound of said part afterrelatching of said part to said impulse element of an extent sufficientto separate said contact members and permit a complete return of saidpart and impulse eleposition, one of said contact members being ment andthe other being mounted in a position to be engaged thereby at the endof the impulse movement of said impulse element, one of said contactmembers being resiliently mounted to reduce the noise of impact.

16. In an electric clock, an oscillating element, an impulse elementbiased for movement in a direction to engage said oscillating elementand increase its amplitude of oscillation, an electromagnet having amovable part, means for yieldingly operating said part in one directionwhen said electromagnet is dcenergized, a latch element carried bycarried by said impulse elesaid part and engaging with said impulseelement to hold it in poised inoperative position while said part is inretracted position, means operable upon said latch to release saidimpulse element when the amplitude of oscillation of said oscillatingelement falls below a selected minimum, contact members operable tocheck movement of said impulse element when released, a circuitincluding said electromagnet and controlled by said contact members,whereby when said impulse element is checked by said members saidmovable part Will be shifted in a direction to carry its latch intorelatched engagement with said impulse element, a resilient bufi'erengaged by said part at the end of its relatching movement for causing arebound of said part after relatching of said part to said impulseelement of an extent sufficient to separate said contact members andpermit a complete return of said part and impulse element to initialposition. one of said contact members being carried by said impulseelement and the other being mounted in a position to be engaged therebyat the end of the impulse movement of said impulse element, one of saidcontact members being adjustable toward and from the other so as to varythe extent of movement of said impulse element before engagement of saidmembers, one of said contact members being resiliently mounted to reducethe noise of impact.

17. In an electric clock, apivoted impulse arm biased for movement inone direction, an electromagnet device having an armature mounted foroscillation in proximity to said arm, said armature being biased formovement in a direction reverse to that caused by said electromagnet, alatch pivoted on said armature and engaging with said arm to hold thelatter against movement in said one direction. a circuit including saidelectromagnetic device, means operable by said arm at the end of' itsmoven'ient when released for changing the condition of said circuit andcausing movement of said armature in a direction to carry said latchinto reengagement with said arm, and a resilient buffer engaged by saidarmature just prior to the reengagementof said latch with said arm forcausing a rebound of said armature after reengagement of said latch withsaid arm suflicient in extent to return the arm sufficiently to restoresaid circuit to initial condition and thus cause a complete return ofsaid armature and arm to initial positions.

18. In an electric clock, an impulse element biased for movement in onedirection, a movable holding member having a latch engaging said elementfor releasably holding said element against movement in said onedirection. means for urging said member in one direction to causemovement of said element in one direction into poised inoperativeposition, said latch being operable to release said element while saidmember remains stationary, means for urging said member in a reversedirection to carry said latch into relatched engagement with saidelement, means rendered operative by said element at the end of itsbiased movement for rendering said second mentioned means eti'ective tocause a movement of said member into relatched enga ement with saidelement, a resilient bufi'er eftective upon said member after movementin a direction to cause its relatched engagement with said element forcausing a rebound of said member after reengagement of said latch withsaid element, said rebound being of an extent sufficient to partiallyreturn said member and element and thus render ineffective the meansrendered effective by said element at the end of its movement in saidone direction, and thus permit complete return of said element and saidmember under the influence of said first mentioned means.

19. In an electric clock, an impulse lever biased for movement in onedirection, an electromagnet having an armature biased into retractedposition, a latch pivotally mounted on said armature and engaging withsaid lever to obstruct movement of said lever in said one direction andhold said lever in poised position when said armature is retracted, acircuit having controlling means operable by said lever at the end ofits movement in said one direction for causing an energization of saidmagnet and an attraction of said armature. a resilient butter forstopping the movement of said armature under attraction and causingrebound oti said armature after reengagement of said latch with saidlever, said rebound, being suflicicnt to cause a partial return of saidarmature and a partial return of said lever sufficient in extent to opensaid circuit, permit a retraction of said armature, and through it areturn of said lever to poised position, and means for operating saidlatch -to release said lever.

20. In an electric. clock, an impulse lever biased for movement. in onedirection. an elec tromagnet having an armature biased into retractedposition,- a latch pivotally mounted on said armature and engaging withsaid lever to obstruct movement of said lever in said one direction andhold said lever in poised position when said armature is retracted, acircuit having controlling means operable by said lever at the end ofits movement in said one direction for causing an energization of saidmagnet andan attraction of said armature, a resilient buffer forstopping the movement of said armature under attraction and causingrebound of said armature after reengage 1 Lil) position, and means foroperating said latch to release said lever, said circuit controllingmeans including a contact device for limiting movement of said lever insaid one direction and adjustable to vary the extent of movement of saidlever in said one direction.

21. In an electric clock, an impulse lever biased for movement in onedirection, an electromagnet having an armature biased into retractedposition, a latch pivotally mounted on said armature and engaging withsaid lever to obstruct movement of said lever in said one direction andhold said lever in poised position when said armature is retracted, acircuit having controlling means operable by said lever at the end ofits movement in said one direction for causing an energization of saidmagnet and an attraction of said armature, a resilient buffer forstopping the movement of said armature under attraction and causingrebound of said armature after reengagement of said latch with saidlever, said rebound being suflicient to cause a partial return of saidarmature and a partial return of said lever suflicient in extent to opensaid circuit, permit a retraction of said armature, and through it areturn of said lever to poised position, and means for operating saidlatch to release said lever, said circuit controlling means including ascrew carried by said lever and adjustable in said onedirection, and acontact device with which said screw engages to limit movement of saidlever in said one direction and close said circuit.

22. In an electric clock, an impulse lever biased for movement in onedirection, an electromagnet having an armature biased into retractedposition, a latch pivotally mounted on said armature and engaging withsaid lever to obstruct movement of said lever in said one direction andhold said lever in poised position when said armature is retracted, acircuit having controlling means operable by said lever at the end ofits movement in said one direction for causing an energization of saidmagnet and an attraction of said armature, a resilient buffer forstopping the movement of said armature under attraction and causingrebound of said armature after recngagement of said latch with saidlever, said rebound being sufiicient to cause a partial return of saidarmature and a partial return of said lever sufficient in extent to opensaid circuit, permit a retraction of said armature, and through it areturn of said lever to poised position, and means for operating saidlatch to release said lever, said circuit controlling means including acontact screw adjustable on said lever in said one direction, and arelatively fixed resilient contact member in the path of movement ofsaid screw with said lever in said one direction so as to variably limitmovement of said lever in said one direction and also close saidcircuit.

23. In an electric clock, a time train, :1

ratchet wheel geared to said time train to drive the same, a crutch, ashaft oscillatably mounted in said crutch and having a groove extendingtransversely across the same, a strip of material having a portionintermediate of its ends fitting closely in said groove, the material ofthe shaft adjacent the groove being upset over said strap to confine thesame within the groove, one end of said strip being formed to engagesaid ratchet wheel and drive the same when said crutch is oscillated.

24. In an electric clock, a time train, a ratchet wheel geared to saidtime train to drive the same, a crutch, a shaft oscillatably mounted insaid crutch and having a groove extending transversely across the same,a

strip of material having a portion intermediate of its ends fittingclosely in said groove, the material of the shaft adjacent the groovebeing upset over said strap to confine the same within the groove, oneend of said strip being formed to engage said ratchet wheel and drivethe same when said crutch is oscillated, said strip being extended fromsaid shaft in a manner to be biased by gravity in a direction to carryits driving portion into contact with the teeth of the ratchet wheel.

25. In an electric clock, a time train, a ratchet wheel geared to saidtime train to drive the same, a crutch, a shaft oscillatably mounted insaid crutch and having a groove extending transversely across the same,a strip of material having a portion intermediate of its ends fittingclosel in said groove, the material of the shaft ad acent the groovebeing upset over said strap to confine the same within the groove, oneend of said strip being formed to engage said ratchet wheel and drivethe same when said crutch is oscillated, said strip being extended fromsaid shaft in a manner to be biased by gravity in a direction to carryits driving portion into contact with the teeth of the ratchet wheel,said crutch having a stop limiting movement of said strip toward theratchet wheel under the influence of gravity.

26. In an electric clock, an oscillating crutch, a time train, a ratchetwheel geared to said time train to drive the same, a shaft mounted insaid crutch for oscillation about an axis parallel to the axis of saidratchet wheel, said shaft having a transversely extending groove in oneside thereof, a strip of ribbon metal having intermediate of its ends aportion reduced in width to closely fit said groove in said shaft, thematerial of the shaft along the groove being upset over said strip toconfine it within the groove, one end of said strip being extendedangularly for driving engagement with said ratchet wheel, the other endof said strip extending sufliciently in the opposite direction tooverbalance said strip and bias it in a direction to carry the angularend into driving engagement with said ratchet wheel.

27. In an electric clock, a time train, a ratchet wheel geared to saidtime train to drive the same, means for imparting increments ofmovements to said ratchet wheel and through it to said time train, aholding pawl engaging with said ratchet Wheel to prevent movementthereof in a reverse direction, said holding pawl comprising a pivotallymounted shaft having a groove extending transversely thereof at one sidethereof, a metal strip disposed intermediate .of its ends in saidgroove, the material of the shaft along the groove being upset againstsaid strip to confine it within the groove and against movement thereon,one end of said strip being extended for contact with the ratchet teeth,and also having another portion bent angularly thereto to serve as aWeight urging said strip into contact with the teeth of said ratchetwheel, the other end of said strip extending beyond the shaft andserving as a stop limiting movement of the ratchet wheel engaging end ofsaid pawl in a'direction toward said ratchet wheel but permittingmovement of the ratchet engaging end of said pawl to some extent intospaces between the teeth of said ratchet wheel.

28. In an electric clock, the combination of a battery, anelectromagnet, a circuit including said battery and magnet, an armature,contact means for said circuit releasably held in open circuit conditionby said armature and when released operable into closed circuitcondition, a buffer spring engaged by said armature when it approachesits attracted position, said armature automatically reengaging saidmeans as it approaches attracted position, whereby said armature duringits rebound from said spring will restore said means to open circuitcondition to permit complete retraction of the armature.

ARTHUR F. POOLE.

